View Full Version : How can I stop electrical noise from entering the audio stream on my laptop?

04-21-2011, 08:22 AM
When connected to the AC power source, my laptop (an Acer 4520) generates a more than acceptable amount of electrical noise through the headphone jack.

Short of buying an external sound card what are my options to put an end to this or is it simple a design flaw?

04-21-2011, 09:48 AM
Do you use the laptop in the boat? What kind of boat do you have?

04-21-2011, 02:03 PM
First you need to pop the cover off, then carefully hover your hand over the motherboard, when you find the really hot part, that is the CPU, now carefully stick your tongue on it. When you stop screaming you won't care so much about the noise.

04-21-2011, 03:21 PM
This should be an easy fix. When running off the internal laptop battery you probably will not have a noise problem but when switching over to the laptop external power supply you get noise. The stereo headphone jack is 3-conductor with a common ground that probably references chassis ground. The stereo RCA input shields/grounds are actually floating or 'above ground' and will not register complete continuity to chassis ground if you check this out. So you want to install a standard stereo RCA ground loop isolator on the auxilary input. This magnetically couples the RCA ground shields via transformers but provides the required DC isolation. No promises, but this should halt the noise coming from the power supply.

Earmark Marine

04-21-2011, 03:27 PM
Guys, I posted my questions above because this guy is a suspected spammer. Who puts as their first post on a boating forum a question about sound on his laptop?

04-21-2011, 03:49 PM
betting he is a spammer.

he probably would not be a suspect if he had posted about viagra or cialis :)